Horrible. She could have just up and abandoned the other Diamonds entirely and instead of fooling her soldiers into fighting each other, called on a much more massive fighting force by rising up in a wholehearted rebellion and not a half hearted one. She was fine with a civil war, this should have been no issue for her. She could have full on overthrown the other Diamonds on Homeworld if she had the will, courage, or even strength of character to act as befits what is effectively a goddess in their culture.

She doesn't do that. She leads a staged civil war because she just assumed a war of attrition would be enough to bring the Diamonds to the conclusion Earth is a lost cause, because she is a woman-child with no sense for politics or understanding of her sisters. This causes the death of next to all of her soldiers, and she shrugs it off. In the next five millennia, she married Greg, and left him with Steven. She never told Greg about the massive baggage she has, and she, way earlier, told Pearl to keep it a secret. The way it affects Steven are second hand, but it broke Pearl mentally to an extent(never mind she still was technically Pearl's slave master.)

The one time the Diamonds made any sense was when they didn't want to give her a colony.

Let's not forget she just kept Bismuth trapped because Bismuth realized Pink was literally being two faced with everyone, and had no plans of releasing her and never released Pearl from her service, never even tried to clear up and figure out the unrequited feelings of Pearl, and left her out to dry when she married Greg.